Product Details
N38 Pot Magnet – Robust Holding Power in a Protective Steel Housing
For applications requiring a dependable holding or mounting magnet with a good balance of strength and cost, the N38 pot magnet is a top choice. The N38 grade (Br 1.24‑1.28 T, BHmax 38‑40 MGOe) offers about 10‑15% more magnetic output than N35, yet remains more affordable than higher grades like N42 or N48. The steel cup not only concentrates magnetic flux to the contact face, multiplying the effective pull force, but also shields the brittle neodymium magnet from impact, corrosion, and demagnetizing fields. These pot magnets are widely used in holding fixtures, magnetic latches, sensors, tool mounting, and industrial assembly jigs. Our N38 pot magnets are manufactured from 100% virgin rare‑earth materials (purity ≥95%) with full process control – from alloy melting to final assembly. The steel cup is precision‑stamped, zinc‑plated or nickel‑plated, and the magnet is securely bonded inside. Standard options include countersunk holes for flush mounting, threaded studs, or plain cups for adhesive bonding. We offer diameters from 10 mm to 80 mm, custom thread sizes, and alternative coatings (epoxy, gold) for specialized environments. Every unit is tested for pull force to ensure consistency, and we provide full certification for quality‑conscious buyers.
Technical Specifications
Why Choose an N38 Pot Magnet for Your Application
Optimized Magnetic Circuit
The steel cup acts as a flux concentrator, focusing the magnetic field onto the contact surface. This design can increase the effective holding force by 30‑50% compared to a bare magnet of the same size, while also protecting the magnet from chipping.
Multiple Mounting Options
Available with countersunk holes (M3‑M10), threaded studs (metric or imperial), or flat back for adhesive bonding. This flexibility simplifies integration into your existing assemblies without custom brackets.
Durable Corrosion Protection
The steel cup is zinc‑plated (Cr3‑free) or nickel‑plated, and the magnet core is Ni‑Cu‑Ni plated before assembly. This dual protection ensures long service life even in mildly corrosive environments.
Quality Built on Full Process Control
Our integrated factory produces both the magnetic core and the steel cup. The N38 magnet is sintered from 100% virgin rare‑earth materials (no recycled scrap) with precise control over alloy composition, grain size, and magnetic orientation. After grinding to the required dimensions, the magnet is Ni‑Cu‑Ni plated to prevent corrosion. The steel cup is stamped, machined, and plated in‑house, ensuring tight dimensional tolerances. The magnet is then securely bonded into the cup using high‑strength epoxy. Every N38 pot magnet is tested for pull force using a calibrated spring gauge, and we sample‑test for salt‑spray resistance (ASTM B117). We provide material test certificates and dimensional reports for each batch. Our IATF 16949 and ISO 9001 systems guarantee consistent quality for industrial OEMs and distributors.
Packaging & Shipping
Each pot magnet is individually wrapped in foam or placed in compartmentalized trays to prevent scratching and magnetism loss. Outer cartons are reinforced for sea or air freight. Lead times: standard sizes 7‑10 days, custom orders 15‑20 days. Free samples available for qualified projects. We support mixed orders and small MOQs.
Export-Ready Packaging & Support
Our strength as a direct manufacturer lies in controlling the entire value chain. The NdFeB alloy is sintered in-house using ≥95% purity raw materials, then precision-ground. The steel cups are stamped, machined, and plated in our facility. This integration allows for rigorous quality checks at each stage-dimensional accuracy (tolerance down to ±0.05mm), coating thickness, and final pull-force verification-ensuring every strong neodymium pot magnet meets specification before shipment.
FAQ
Q1: What does "N38" signify in an N38 pot magnet, and why is this grade chosen for pot designs?
A1: N38 denotes a sintered NdFeB magnet with energy product 36–40 MGOe and remanence 1.22–1.26 T. It offers a balanced cost‑performance point – lower than N42 but higher coercivity than N35 (Hcj ≈12 kOe). For pot magnets, the steel shell increases holding force by redirecting flux to the working face. N38 is popular because it provides sufficient pull (e.g., 40–50 kg for a 32 mm pot) without excessive brittleness or high‑temperature sensitivity (max 80°C). It is a common choice for industrial holding and mounting.
Q2: How does the steel pot shell affect the magnetic field distribution of an N38 magnet?
A2: The low‑carbon steel shell acts as a flux concentrator. It shields the sides and back, forcing magnetic flux to exit only through the exposed face – nearly doubling surface field versus a bare N38 magnet of the same size. The shell also minimizes stray field, reducing interference with nearby electronics. However, it adds weight and limits max temperature because the steel can saturate at high flux. Optimal shell thickness (2–3 mm) ensures maximum pull without degrading the internal magnet's performance.
Q3: What is the maximum holding force of a typical N38 pot magnet, and how is it measured?
A3: Holding force depends on diameter and contact surface. For a 25 mm dia. N38 pot, pull force ≈25 kg against a thick steel plate; 32 mm → ≈45 kg; 40 mm → ≈70 kg. Force is measured with a tensile tester on a clean, flat steel surface (≥5 mm thick). Actual force drops sharply with air gap – a 0.1 mm gap reduces force by ~30%. Always derate by 50% for dynamic applications and account for surface roughness.
Q4: Can an N38 pot magnet be used above 80°C? What alternatives exist?
A4: Standard N38 has an max operating temperature of 80°C; above that, irreversible flux loss occurs. For higher heat, choose N38H (120°C), N38SH (150°C), or N38UH (180°C) – these have higher intrinsic coercivity but slightly lower remanence. The steel shell also expands with heat, potentially loosening the magnet. For occasional 100°C exposure, N38 may still work but with a 10‑15% force reduction. Specify a high‑temp grade for continuous hot environments.
Certifications
